Recently, as a rewritable nonvolatile memory, the magnetic random access memory (hereinafter called the MRAM) including magnetoresistive effect elements arranged in a matrix is noted. The MRAM uses combinations of magnetization directions of two magnetic layers to memorize information and detects resistance changes (i.e., current changes or voltage changes) between when the magnetization directions of the magnetic layers are parallel to each and when they are antiparallel to each other to read the memorized information.
As one of the magnetoresistive effect elements forming the MRAM is known the magnetic tunnel junction (hereinafter called the MTJ) element is known. The MTJ element includes two ferromagnetic layers stacked with a tunnel insulating film formed therebetween and uses the phenomenon that different tunnel currents flow between the magnetic layers via the tunnel insulating film, based on relationships of the magnetization directions of the two ferromagnetic layers. That is, the MTJ element has a lower element resistance when the magnetization directions of the two ferromagnetic layers are parallel to each other, and when they are antiparallel to each other, has a higher element resistance. Such two states are related with data “0” and data “1”, whereby the MTJ element can be used as a memory element.
The following is example of related: Japanese Laid-open Patent Publication No. 2001-196659.
To improve the reliability of magnetic memory devices and other electronic devices using magnetoresistive effect elements, structures which can improve the reliability of the magnetoresistive effect elements and manufacturing method which can stably manufacture the magnetoresistive effect elements of high reliability are expected.